Electric musical instrument



Feb. 9, 1937. F WATERS 2,070,344 v ELECTRIC MUSICAL. INSTRUMENT Original Fim Aug.' 14. 1931 EVEN-ron BY AT/ToRNEZj/my/m Patented Feb. 9, 1937 UNITED STATES PATENT OFFICE Application August 14, 1931, SeriaiNo. 556,969 Renewed June 7, 1935 l 17 Claims.

This invention relates to electric musical instruments, and more particularly to a musical instrument that may 4be operated in conjunction with a radio receiver or with an electric 5 phonograph.

Among the objects of my invention are to provide an electric musical instrument which is simple, practical and of inexpensive construction; one that will be easy to operate, capable of simple and dependable control, and well adapted to meet the varying requirements of production of music, capable of being readily and conveniently adapted to the production of music in accompaniment or in conjunction with another musical 1nstrument or music-reproducing instrument; one in which the range of available notes maybe readily and dependably shifted, and correction or determination of pitch may be easily and quickly effected with a high degree of accuracy. o The invention accordingly consists in the combinations of elements, arrangements of parts and features of construction as will be exemplied in the structure to be hereinafter described and the scope ofthe application of which will 'be indicated in the following claims.

u In the accompanying drawing in which are shown several of the various possible embodiments of my invention:

Figure 1 is a diagrammatic representation of my musical instrument coacting with, for example` a radio receiver or an electric phonograph;

Figure 2 is a diagrammatic representation, particularly of a preferred form of electrical circuit and devices illustrating certain features of L, my invention,

Figure 3 is a plan view, partly broken away, of an embodiment in the form of a violin of certain features of my invention, and,

Figure 4 is a plan view, partly broken away, of another embodiment in the form of a violin of certain features of my invention.

Similar reference charactersrlefer to similar parts throughout the various views of the drawin teferring to the drawingz-In Figure 1 is shown a radio receiver or electric phonograph, generally indicated at I, including one or more stages of audio-frequency amplification diagrammatically indicated at II, and .radio-frequency\\ uning and detecting means (in the case ci a` radio receiver) or electromagneticspiek-up means (in the case of an electric phonograph) diagrammatically indicated at I2. The audio-frequency amplifier II may be used either with or without the radio receiver or phonograph pick-up means I2, by manipulation of a control switch generally denoted I3. An external connection to the audiofrequency ampliiier I I is provided by a jack construction I4 connected to amplier II by wires I5a and I5b. 6

Directly connected to the output of the audiofrequency amplifier II by means of interconnecting Wires I 6a and Ilib, is a loud-speaker or other translating device I I. For connection with the jack I4 and hence to the audio-frequency aml0 plier II and the energy-translating device I1, is a plug construction I8 with its leads I9a and ISIb connected to my electric lmusical .instrument diagrammatically indicated at 2|). -The instrument preferably comprises a box-like containu er 2| having along one edge thereof an exposed keyboard 22 adapted for manual manipulation of its individual keys, and also exposed control knobs 23 and 24 for respectively controlling the keyboard shift and pitch-correcting mechanisms to be more clearly described hereinafter. Within the container 2| and electrically connected to the keyboard 22 and the keyboard shifting control 23 and pitch correcting control 24, there is enclosed the mechanism of the electric musical instrument 20 which, together with certain of its possible coactions with the devices II) and II, will be described more fully hereinafter.

Considering now certain of the devices embodied in the instrument 20 of Figure 1, 30 reference may first be made to Figure 2 in which the cabinet or the casing 2l is diagrammatically indicated together with the parts that are therein contained or associated therewith. The keycated in Figure 2 in the form of a suitable number of individual keys arranged preferably like the keys of a piano, each including a contact member 22n adapted, in any suitable manner, to engage and contact with a resistance wire or other suitable conductor of relatively low conductivity indicated at 25. 'I'he contacts 22 carried by the individual keys are interconnected by a conductor 2B. Thus, as the keys of the keyboard 22 are depressed, the amount or ohmic value of 45 the effective resistance in the circuit in which the keyboard 22 is included may be correspondingly varied.

The electrical portions of the keyboard 22 are connected in an electrical circuit which, while referring to Figure 2, may be traced as follows:- From one terminal of a suitable source oi' electrical energy, such as aV battery 21, conductor 28, pitch-regulating or pitch-correcting control 24, keyboard shifting control 23, conductor 29, re-

sistance 25 with which a contact 22a may engage upon depression of the corresponding key, conductor 26, conductor 30, a condenser 3|, conductor 32, the primary winding 33 of a suitable transformer of which the secondary winding is indicated at 34, and then by way of conductor 35 and backito Ithe other side or terminal of battery 21.

Bridged across condenser 3I, by conductors 36-31, is a gaseous discharge tube or device 38 through which the condenser 3|, upon being suit- The terminals of ably charged, may discharge. the secondary winding 34 of the transformer 33-34 are connected by conductors Illa and I 9b to the tip and sleeve respectively of the plug I8 (see also Figure 1).

As already above described, plug I8 may be inserted into jack I4 (see Figure 1) for coaction with `the audio-frequency amplifier II and the loud-speaker I1. Or I may use plug I8 to coact with a jack 39 (see now Figure 2) associated with a separate audio-frequency amplifier diagrammatically indicated at 40, the output of which is transmitted by conductors 4Ia and 4Ib to a suitable translating, recording or like device 42 which may also take the form of a loudspeaker.

As the keys 22b of the .keyboard 22 are depresseddn appropriate sequence much in -the same manner as the keys of a piano may be actuated for producing music or the like, the

and discharging repeats itself during the intervalv of time that the particular key remains depressed and its repetition is at a rate dependent upon the voltage applied to the condenser 3I for charging 1 the latter. The parts are preferably so proportloned and the average voltage so selected that this repetitionetakes place at an audio-frequency rate.

As a consequence of this repeated action, the current through the primary winding 33 of transformer 33-34 undergoes variations at a corresponding frequency or rate, producing in the secondary winding 34 a current or potential that likewise varies at this audio-frequency rate and 7 which is amplified by the amplifier 4I! and translated into sound of corresponding pitch by the translating device 42 where the latter functions, for example, as a loud-speaker; or, with the arrangement of Figure 1, the output of transformer 33-34 is amplified by the amplifier I I and translated by the device I1.

If, however, a different key 22b is depressed, the circuit of condenser 3| is again closed but due to the inclusion in this circuit of a diierent portion or fraction of the resistance 25, the voltage applied to the condenser 3| is now dlierent and the rate of charge and discharge of the condenser takes place now at some other or different audio-frequency rate,` corresponding in turn to the production of a different note in the musical scale. Thus the keyboard 22, which/may be provided With as many keys as is/dsirei 'may be manually operated to causewthe production of notes in any desired sequence and thus to play any tune or melody or the like as may be desired.

Insofar ascertain features of my invention are concerned, it is to be understood that the oscillation generator, above described as of 'the con'- denser charge and discharge type, is to be understood to be merely illustrative and that any otherl suitable form of oscillation generator may be employed.

In order to simplify the construction and to make it possible to use a minimum or relatively small number of keys, such as a number equivalent to several octaves, thus giving the keyboard itself a relatively small or narrow range, while at the same time to make it possible to cause this small range keyboard to have a much greater i,

range than is inherent in itself, I have provided the keyboard shifting control 23 above briey mentioned in connectionwith both Figures 1 and 2. This control includes a contact arm 43 vpreferably manually controlled in any suitable manner as by means of a rotatable knob 23a; contact arm 43 coacts with xed contacts 44a, 44h, 44c and I4d connected by suitable conductors to equi-distantly spaced points in a suitable resistance 33 and, as above pointed out, the control 23 is .in the above described condenser charging circuit. i

By means of the control arm 23a and its coactingy parts, I may include in this circuit one or more or none of the sections of the resistance 44, each section being of such a resistance value that it causes shift of the complete range of the keyboard 22 by exactly one octave. Illustratively I have shown three such sections of resistance to eict a` shift along the musical scale of from one to three octaves of the complete or inherent range of the keyboard 22 itself.

In 'operating the instrument, as by suitably ngering the keyboard 22, I may, during the playing of any selection, extend the range of the keyboard 22 where and when necessary and either upwardly or downwardly of 'the musical scale by correspondingly and appropriately setting the control 23. Y Or, if it is desired to play any given selection that falls within the inherent range of the keyboard 2 2 at a lower or higher standard in the musical scale, I first set the control 23 to the point desired and then proceed with the manipulation of the keyboard 22.

Where my musical instrument is arranged as in Figure 2 to coact with its own amplifier 40 and loud-speaker 42, or whereI it is arranged as in Figure 1 toutilize rthe amplifier II- and the translating device or loud-speaker I 'I of a radio receiving set o'r, by way of further example, of an electric phonograph, and it is desired to play the instrument or to accompany even the music reproduced by the phonograph from a record, or by the radio receiving set as the latter receives, detects, ampliiies and translates broadcast music, this keyboard shifting control 23makes it possible to carry on the accompanimen not only throughout the entire range of scale of the particular. piece being accompanied even though the keyboard 22 may be of limited range, but also to select or determine at will whether the accompaniment being played is one or more or no octaves higher or lower. Particularly under these circumstances, pitch governing control 24, already above mentioned ln connection with both Figures 1 and 2, as well as when my instrument is used alone, is of great importance; this control 24 includes a manually operable variable resistance taking the form preferably of a contact arm 45 operated by the control knob` 24 and in slicable engagement with a resistance' 46 so that relatively fine changes in resistance in the above described condenser-charging circuit may be made. By means of the control 24, my instrument may be properly and quickly pitched or brought into tune. Also by means of the control 24 I may readily and conveniently maintain the proper tune or pitch of the instrument as against such pitch-changing factors as, for example, variation or change in the voltage of the source 21, temperature changes in the circuit or parts thereof, or even changes in the operating characteristics of the condenser 3| or of the discharge tube 38 or both.

In Figure 3 I have shown a possible modified form of certain features of myA invention and more particularly I have there shown my musical instrument in the form of a violin; the cabinet 20 of Figures 1 and 2 has been given the form or shape of a violin casing 2| and within the casing are contained, all as diagrammatically indicated in Figure 3, the condenser-charging circuit and its parts, comprising the battery 21, the pitch governing control 24, the octave shifting control 23, condenser 3| with its discharge device 38, the transformer 33-34, and also the amplier 40 and the loud-speaker 42. ual control of the emitted notes however is achieved by fingering as in a violin, a single string 41 of conducting material suitably anchored at its right hand end as at 43 and connected at its left hand end to a suitable tensioning device 49. The conducting string 41 overlies the arm 50 of the violin and the latter carries, exposed on its upper surface, a resistance 5I which underlies the conducting string 41. Resistance 5I and the string 41, when the latter is depressed, are connected in series with each other and also in series with the above described condenser-charging circuit, being positioned electrically in the same position as is the keyboard 22 of Figure 2.

As the string 41 is ngered to depress it and cause it to contact with different portions of the resistance 5l the pitch of the emitted note is correspondingly changed in a manner and by an action that will now in view of what has been above set forth in connection with Figures 1 and 2, be clear. In Figure 4 I have shown the musical instrument also in the form of a violin but I have associated therewith a cord I9 and lilb and plug I8 leading from the secondary winding 34 of the `transformer so that the violin instrument may be associated with a radio receiving set or an electrically reproducing phonograph for utilization of the amplifier and loud-speaker thereof or for accompanying the music produced by these instruments. I have also shown the plug 52 and its associated cord 53il and 53b leading from the conductors 28 and 35 so that the instrument may be connected to an external source of energy supply generally denoted 55 as by plugging into the jack structure 54. The external source of supply 55 may be in the form of a battery or it may be a rectier within or without a radio receiver cabinet.

Various of the advantages and methods of control and use as described in connection with Figures'l and 2 may be achieved and carried out with the arrangements of either Figures 3 or 4 or both, as is believed will be clear in view of what has been set forth above in connection with Figures 1 and 2.

Thus it will be seen that there has been provided in this invention an electric musical instrument in which the various objects hereinbefore noted, together with many practical advantages, have been successfully achieved. Furthermore, it will be seen that the apparatus is characterized by a wide and convenient flexibility of control and use and that such results and advantages as these are achieved in a thoroughly practical, inexpensive, and dependable manner. It will be seen also that the construction is simple, practical and well adapted to-the varying conditions of actual use.

As many possible embodiments may be made of my invention, and as many changes might be made in the embodiments hereinbefore set forth, it is to be understood that my disclosures are to be taken in an illustrative and not in a limiting sense.

I claim:

1. In an electrical musical instrument, in combination, means for producing electrical impulses at an audio-frequency rate, means for sequentially changing the rate of said impulses throughout a desired range of operation, and means for uniformly shifting the range of operation of said last mentioned means at least an amount equivalent to one complete octave of the musical scale.

2. In an electricalmusical instrument, in combination, an oscillation generator, a keyboard control therefor arranged to vary the frequency of the electrical oscillations developed by said generator and to cause the sounding by a suitable translating device connected thereto of a plurality of audible notes of predetermined respective pitches, and means for shiftingthe range of the keyboard control of said generator by an amount equivalent to a complete octave oi the musical scale.

3. In an electrical musical instrument, in combination, an oscillation generator, a keyboard control therefor arranged to vary the frequency of the electrical oscillations developed by said generatorv and to cause the sounding by a suitable translating device connected thereto of a pluralityof audible notes of predetermined respective pitches, means for shifting the range of the keyboard control of said generator so as to result in a corresponding shift in the audible range of the output of the translating device along the musical scale one or more complete octaves, and means for regulating the frequency of said oscillation generator so as to correct the pitch of the audible s energy output of said translating device.

4.. In an electrical musical instrument, in combination, an oscillation generator comprising an electrical condenser and a glow-discharge tube shunted thereacross, a keyboard control therefor comprising an electrical resistance element, means including a variable electrical resistance connected to said keyboard control electrical resistance element for shifting 'the range of the keyboard control of said generator so as to result in a corresponding shift along the musical scale in the nl O nected thereto arranged to cause the sounding by said translatingdevice'of a plurality of audible notes of predetermined respective pitches, and means comprising a variable electrical resistance connected With said keyboard control electrical resistance element and with said oscillation generator for correcting the frequency of the electrical oscillations developed by said generator and the pitch of the audible energy output of said translating device.

. 6. In an electrical musical instrument; in'combination, means comprising an electrical condenser and a glow-discharge tube connected thereto for/.producing electrical energy varying `at an audio-frequency rate, translating means responsive to the energy produced by said firstmentioned means, means operable at will for causing changes in' the frequency of the energy produced by said first-mentioned means throughout a desired range, and means for alteringthe position ofA this desired range in thel energy spectrum by one or more complete-octaves of the musical scale. l

7. In an electrical musical instrument, in combination, means for producing electrical energy varying at anaudio-frequency rate, translating means responsive tothe energy produced by said first-mentioned means, means operable at will for causing changes in the frequency of the energy produced by said mst-mentioned means, and means for shifting the range of operation of said last-mentioned means an amount equivalent to at least one octave in the musical scale.

8. In an electrical musical instrument, in combination, means for producing electrical energy varying at an audio-frequency rate, translating means responsive to the energy produced by said first-mentioned means, means operable to cause changes in the frequency of the energy of said first-mentioned means so as to cause responsive changes in the audible output energy of said translating device in accordance with diierent notes in the musical scale and means for shifting the frequency range of said first-mentioned means an amount equal to at least one octave of the musical scale.

9. In an electrical musical instrument, in combination, an oscillation generator comprising an electrical condenser and a glow-discharge tube shunted across said condenser, means operatively associated withsaid generator for producing numerous musical notes of diiferent respective' pitches, and means for collectively changing the pitch of the note-producing means by an amount equivalent to one or more octaves of the musical scale while maintaining-the pitch intervals thereof.

10. In an electrical musical instrument, in combination, means including an electrical condenser and a glow-discharge tube shunted thereacross for producing electrical energy varying at an audio-frequency rate, electrical resistance means for changing at Will and sequentially the audio-frequency output of said means, said second-mentioned means including twoy coacting members, one of which is in the form of a string adapted to be ngcred like a violin string, and means for shifting the range of operation of said iirst-mentioned means by one or more octaves of the musical scale.y

11. In an electrical musical instrument, in combination, means including an oscillation generator for producing a plurality of individual musical notes throughout a desired range in the musical scale, and means for altering collectively the positions in the musical scale of said note producing means by at least one octave of the musical scale.

12. In an electrical musical instrument, in combination, means including an oscillation generator comprising an electrical condenser and a glow-discharge tube shunted thereacross, an electrical resistance element connected to said means having a keyboard control therefor arranged to cause the sounding of a plurality of notes of predetermined respective pitches, and pitch regulating means fo-r said instrument comprising an electrical resistance element serially connected with said first-mentioned electrical resistance element whereby said instrument may be accurately tuned. f

13. In an electrical musical instrument, in combination, an oscillation lgenerator including an electrical condenser and a glow-discharge tube connected thereto, electrical resistance means connected to said generator `for producing numerous individual notes of different pitches, and electrical resistance means connected toasaid last-mentioned means for collectively correcting the pitches of the numerous notes against the effect of variables in the generator circuit.

14. In an electrical musical instrument, 'in combination, an oscillation generator comprising an electrical condenser and a glow-discharge tube connected thereto, means including an electrical resistance element for producing numerous notes of different pitches,`and means including an electrical resistance element for collectively modifying the pitches of numerous notes toharmonize the instrument with another instrument.

15. In an electrical musical instrument, in combination, means including an electrical con-- denser and a glow-discharge tube for producing electrical impulses at an audio-frequency rate, means including an electrical resistance element `lfor sequentially changing the rate of said impulses throughout a desired range of operation, and means including an adjustable electrical resistance element serially connected with said last-mentioned means for shifting the range of operation of said means whereby the distance between the limits of operation remains substantially constant.

16. In an electrical musical instrument, in combination with an oscillation generator including an electrical condenser and a glow-discharge tube connected therewith, means including an electrical resistance element for sequentially producing a number of musical notes of different pitches, and electrical resistance means for collectively changing the pitches of said musical notes while maintaining their pitch differences.

17. In an electrical musical instrument, in combination with an oscillation generator comprising an electrical condenser and a glow-discharge tube connected therewith, electrical means including an electrical resistance element for producing a number of musical notes of different pitches, said means including two coacting members one of which comprises a group of electrical contactors corresponding to the numerous musical notes and the other of which comprises the resistance element.

w HARRY F. WATERS. 

